Masturbating just before sex to make sure you last as long as possible.
I was almost jizzin in my pants when she was grindin on me in club, so I had to have a quick tactical wank in the toilet before I nailed her.
Masturbation a period of time prior to intercourse to allow the participant to last longer before ejaculation. Also known as "Strategic wank"
"Err, Not tonight love"
The masturbation used right before having sex. Used to ensure that a cock-slap does not occur. As made famous by The Inbetweeners.
Simon: What if I can't get it up
Jay: Nah, don't worry, nip off and have a tactical wank now
A tactical wank is one where you manage to slip away in an awkward or boring situation to masturbate in a quick time frame and manage to get back without anyone noticing that you had gone away. Further more people must not have knowledge of what has just taken place. A more informal slang term for this is "tac wank"
*R slips back hoping no one has notices his absence*
"Dude, we know that look, you have just been for a tactical wank haven't you."
"Where have you been son, we were having an important dinner discussion about poor university grades?"
*cough* No where, I just needed a minute."